docs: def Stichlmair_flood(Vl, rhog, rhol, mug, voidage, specific_area, C1, C2, C3,
                       H=1.0):
      r'''Calculates gas rate for flooding of a packed column, using the
      Stichlmair [1]_ correlation. Uses three regressed constants for each
      type of packing, and voidage and specific area.
  
      Pressure drop is given by:
  
      .. math::
          \frac{\Delta P_{irr}}{H} = \frac{\Delta P_{dry}}{H}\left(\frac
          {1-\epsilon + h_T}{1-\epsilon}\right)^{(2+c)/3}
          \left(\frac{\epsilon}{\epsilon-h_T}\right)^{4.65}
  
      .. math::
          h_T = h_0\left[1 + 20\left(\frac{\Delta Pirr}{H\rho_L g}\right)^2\right]
  
      .. math::
          Fr_L = \frac{V_L^2 a}{g \epsilon^{4.65}}
  
      .. math::
          h_0 = 0.555 Fr_L^{1/3}
  
      .. math::
          c = \frac{-C_1/Re_g - C_2/(2Re_g^{0.5})}{f_0}
  
      .. math::
          \Delta P_{dry} = \frac{3}{4} f_0 \frac{1-\epsilon}{\epsilon^{4.65}}
          \rho_G \frac{H}{d_p}V_g^2
  
      .. math::
          f_0 = \frac{C_1}{Re_g} + \frac{C_2}{Re_g^{0.5}} + C_3
  
      .. math::
          d_p = \frac{6(1-\epsilon)}{a}
  
      Parameters
      ----------
      Vl : float
          Superficial velocity of liquid, Q/A [m/s]
      rhog : float
          Density of gas [kg/m^3]
      rhol : float
          Density of liquid [kg/m^3]
      mug : float
          Viscosity of gas [Pa*s]
      voidage : float
          Voidage of bed of packing material []
      specific_area : float
          Specific area of the packing material [m^2/m^3]
      C1 : float
          Packing-specific constant []
      C2 : float
          Packing-specific constant []
      C3 : float
          Packing-specific constant []
      H : float, optional
          Height of packing [m]
  
      Returns
      -------
      Vg : float
          Superficial velocity of gas, Q/A [m/s]
  
      Notes
      -----
      A numerical solver is used to solve this model.
  
      Examples
      --------
      Example is from [1]_, matches.
  
      >>> Stichlmair_flood(Vl = 5E-3, rhog=5., rhol=1200., mug=5E-5,
      ... voidage=0.68, specific_area=260., C1=32., C2=7., C3=1.)
      0.6394323542746928
  
      References
      ----------
      .. [1] Stichlmair, J., J. L. Bravo, and J. R. Fair. "General Model for
         Prediction of Pressure Drop and Capacity of Countercurrent Gas/liquid
         Packed Columns." Gas Separation & Purification 3, no. 1 (March 1989):
         19-28. doi:10.1016/0950-4214(89)80016-7.
      '''
      guess =  [Vl*100., 1000.0]
      return newton_system(_Stichlmair_flood_f_and_jac, x0=guess, jac=True,
                           args=(Vl, rhog, rhol, mug, voidage, specific_area, C1, 
                           C2, C3, H), ytol=1e-11)[0][0]